Combination external and internal container seal



Aug. 15, 1967 HANSON 3,335,893

COMBINATION EXTERNAL AND INTERNAL CONTAINER SEAL Filed June 16, 1965alum;

United States Patent Ofiice 3,335,893 Patented Aug. 15, 1967 3,335,893COMBINATION EXTERNAL AND INTERNAL CONTAINER SEAL Arnold E. Hanson, 2940Lorain Road, San Marino, Calif. 91108 Filed June 16, 1965, Ser. No.464,355 11 Claims. (Cl. 215-46) This invention relates to container capsand more particularly to a container cap with external and internalseals.

Various forms of caps have been utilized to seal containers such asglass or plastic bottles holding beer or other carbonated beveragesunder pressure. Under such conditions it is very desirable to employ acap which Will maintain a reliable seal and yet may be quickly removedwhen it is desired to discharge contents from the bottle.

One of the most effective types of container seals used heretofore is atubular plug of cork or rubber having a diameter slightly larger thanthe inside diameter of a container neck and which is forcefully fittedthereon. Because of the stiffness of the plug inside the container neck,and the very tight seal obtained, a bottle-opener must be used todisengage the plug and remove the seal. In some cases, the surface ofthe cap is scored to form score lines of least resistance which allows aripping or tearing of a portion of the cap along the score lines so asto effect removal of the cap from the container. How ever, the scorelines have a tendency to weaken the cap, thereby making this arrangementsomewhat less than desirable when it is required to reliably sealcontainers under pressure.

It is, therefore, an object of the present invention to provide areliable seal for containers which may be readily removed.

Another object of this invention is to provide a reusable seal forcontainers.

A further object of this invention is to provide a cap with a break awayseal wherein the sealing capability of the cap is not impaired.

A still further object of the present invention is to provide aresilient cap for containers with an integral internal and external sealand wherein the container may be readilyunsealed.

Other objects and advantages of this invention and a fullerunderstanding of the nature thereof may be had by referring to theclaims and to the following detailed description taken in conjunctionwith the accompanying drawings.

FIGURE 1 is a partial schematic illustration of a cap with a break awayseal being removed from a container.

FIGURE 2 is a plan view showing the cap formed with a break away sealarea and a crimped skirt.

FIGURE 3 is a sectional view illustrating the cap in sealing engagementwith a container, the cap having a smooth skirt.

FIGURE 4 is a fragmented elevational view of a cap constructed accordingto the present invention in sealing position on a container.

FIGURE 5 is a sectional view illustrating an alternative embodiment.

As is illustrated in the drawings, and as will be more specificallydescribed, the invention contemplates a cap for containers having a neckrim wherein the cap includes an external and an internal seal, and ispreferably formed of a resilient material such as polyethylene,polypropylene or polystyrene as an integral unit. The internal seal isformed of a plug-like 'wall which resiliently and securely seals withinthe container neck and which may be readily removed when desired. Thisis accomplished by a number of resilient fins which extend inwardly froman outside wall of the plug and allow the plug to easily enter the neckof the container and form an efiicient seal therewith.

In the preferred embodiment of the invention one portion of the cap isformed with a thin wall providing a path of least resistance to tearing.This thin wall section is formed by a cavity in the cap, thus allowingthe strength of the cap to be maintained.

In another embodiment the cap is formed with an integral lift tab whichflexes the cap to disengage the cap from the neck rim and to therebyremove the plug from within the container neck.

Referring now to FIGURE 1 there is shown a container cap 10 which hasjust been removed from a container 11 having a neck rim 12. Thecontainer cap 10 has a skirt 13, slightly flared and forming a sealaround the neck rim 12, and a plug 14 to enter and seal inside a neck 15of the container 11.

The plug 14 includes a wall 16 projecting from a floor 17 of thecontainer cap 10, and a number of fins 18 extending radially from thewall 16 to the inner portion of the plug 14. The fins 18 strengthen theplug 14 so that when the cap 10 is placed on the container 11 the Wall16 will be securely seated against the inner portion of the containerneck 15. In addition to strengthening the plug 14, it may be noted thatthe fins 18 are not interconnected so as to allow the wall 16 to yield,and thereby permit the cap 10 to be readily placed on and removed fromthe container 11.

In FIGURE 1 the cap 10 is shown as having been just removed from thecontainer 11 by grasping a tab 19 between a thumb 20 and a forefinger 21of a hand 22 and by pulling upwardly to tear through a portion of theskirt 13 to release the firm engagement of the skirt 13 With the neckrim 12. It can readily be seen that the tab 19 is an extension of theskirt 13, and if desired, instead of forming an extension the skirt 13itself may be formed with serrations or other gripping surfaces to allowthe gripping of the skirt and tearing away of the skirt seal.

FIGURE 2 illustrates the cap 10 having a top surface 23 with a depressedcavity 24 formed in a portion of the surface 23. Extending from thecavity 24 is the tab 19 with a number of serrations 25 provided as agripping surface thereon. As shown in FIGURE 2 the skirt 13 has a seriesof crimps 26 molded therein to increase the strength of the skirt 13 andto assure a snap positive seal as the skirt 13 is forced over the neckrim 12. It is, of course, not necessary that the crimps 26 always beformed in the skirt as they may only be necessary when it is required toseal containers under extreme pressures. In FIG- URE 3 there is shown acontainer cap 30 having a smooth noncn'mped skirt 31 which firmly gripsthe neck rim 12 of a container 11. In the magnified view of FIGURE 3 theskirt 31 is shown as terminating in a lip 32 frictionally engaged andseated beneath the neck rim 12. In all other aspects the container cap30 is constructed similar to the cap 10. That is, the cap 30 has a topsurface 23 in wln'ch there is formed a cavity 24, the cavity 24extending from the top surface 23 and along a portion of the skirt 31.It may be noted from FIGURE 3 that forming the cavity 24 along a portionof the top surface 23 is a thin wall section 33 which is thinner thanthe adjacent wall sections forming the top surface 23. Similarly, a thinwall section 34 which is thinner than the adjacent wall portions of theskirt 31 provides the cavity 24 along the skirt 31. This is clearlyshown in FIGURE 4 where the thin wall section 33 is illustrated belowadjacent portions of the top surface 23, the thin wall section 33continuing along the skirt 31 in a depressed wall section 34 to thusform the cavity 24. The thin wall section 34 on the skirt 31 ends in atab 19 with the gripping serrations 25.

It can be seen that the thin wall sections 33 and 34 provide lines ofleast resistance to tearing at skirt edges 35, 36 and at top surfaceedges 37, 38. Although the edges 35, 36 and 37, 38 provide a lowresistance tea-ring path along the skirt 31 and a portion of the topsurface 23, they do not lessen the sealing qualities of the cap. This isevident from FIGURE 3, where it is seen that the plug 14 seals insidethe container neck 15, while the skirt 31 and the lip 32 firmly grasparound the rim 12, with the thin wall sections 33 and 34 forming only avery small part of the seal. Also, since the cavity 24 is molded in asthe cap 30 is formed, the cavity 24 presents a very strong channel-likestructure when viewed from inside the container 11. Therefore, byplacing the thin wall sections 33 and 34 on the neck rim 12 where theyare removed from direct pressures from inside the container 11, and inview of the structurally sound channellike section formed by the cavity24, the sealing qualities of the caps and 30 have not in any way beendiminished by the formation of a break area thereon. However, the cavity24 does provide the low tearing resistance edges 35, 36, and 37, 38, andby gripping the tab 19 at the serrations and pulling upwards the thinwall section 34 and 33 can be torn away from the skirt 31 and along aportion of the top surface 23. As diagrammatically shown in FIGURE 1,this operation loosens the grip of the skirt 31 or 13 on the neck rim 12sufliciently to allow continued pulling on the tab 19 to extract theplug 14 from within the container 11, without the tab detaching from thetop surface 23.

Referring again to FIGURE 3, there is clearly illustrated the plug 14having the wall 16 in firm sealing engagement with container neck wall39, the plug 14 also including four fins 18 which extend radially inwardfrom the wall 16. The fins 18 not only strengthen the plug 14 tomaintain the wall 16 in sealing engagement with the container neck wall39, but the fins 18 also allow more even yielding of the wall 16,thereby permitting the plug 14 to be readily inserted into and removedfrom the container 11.

As an example of container caps formed in accordance with the principlesof the present invention, the following table lists the absolute andrelative dimensions of the important portions thereof tor several typesof plastic materials. It is understood that other types of resilientmaterial may be employed and that future thermoplastic developments andimprovements could permit, in accordance with the principles hereindisclosed, the formation of thinner wall cross sectional areas than ispossible at this time.

It has been determined that forming the cap of polypropylene provides avery thin wall section which enables a quick metal-like shear to beobtained when the tab is pulled to break the seal. Somewhat similaralthough slightly more elastic results are obtained with polyethylenebecause of the plia-bility and toughness of polyethylene when formed inrelatively thin sections.

FIGURE 5 illustrates an alternative arrangement wherein container cap 40is shown in sealing position on a container 11 having a neck rim 12. Thecap 40 also includes a plug 14 with a wall 16 maintained by the fins 18in resilient sealing engagement with a container neck wall 39. A skirt41 extends from a top surface 42 and firmly grips the neck rim 12, witha lip 43 securely seated beneath the rim 12. Depending from one smallportion of the skirt 41 is a leverage tab 44 which has a grippingsurface 45 at one end thereof.

It is evident that by lifting up the leverage tab 44 to unseat the lip43 from beneath the rim 12 and to also thereby flex the skirt 41 fromits gripping engagement with the rim 12, the cap 40 which is formed of aresilient material may be readily removed from sealing engagement withthe container 11. Depending on the density of material chosen for thecap 40, a washer-like seal may be required to efiiciently cap and sealthe container 11. In such circumstances, there is provided an annulargroove 46 formed in the container cap 40 immediately above a top ledge47 of the neck rim 12. Within this annular groove 46 there is imbedded aresilient ring or washer 48 which is so sized as to be compressed by thetop ledge 47 when the container cap 40 is placed on the container 11.While in most cases the washer 48 is not required, a similar arrangementcan be provided for the embodiments shown in FIGURES l-4.

Although the drawings and specification present a detailed disclosure ofpreferred embodiments of the present invention, it is to be understoodthat the invention is not limited to the specific forms disclosed, butcovers all modifications, changes and alternative constructions fallingwithin the scope of the principles taught by the invention.

I claim as my invention:

1. An external and internal seal for containers such as bottles having aneck rim comprising:

an external cap including a skirt terminating in a lip,

said skirt flexed to firmly grip said rim with said lip frictionallyseated beneath said rim;

a wall depending from said cap and protruding within said container insealing engagement with said neck;

a tab projecting from said flexed skirt; and

a thin wall section in said cap extending along said skirt to said tabforming a path of least tearing resistance to allow the lifting of saidtab to break away said skirt and disengage said wall from inside saidcontainer neck.

2. An external and internal seal for containers such as bottles having aneck rim comprising:

an external cap including a skirt terminating in a lip,

said skirt flexed to firmly grip said rim with said lip frictionallyseated beneath said rim;

a wall depending from said cap and protruding within said container insealing engagement with said neck;

a plurality of fins radially extending inwardly from said wall toresiliently seat said wall against said container neck; and

a thin wall section in said cap extending along a portion of said skirtand forming a path of least tearing resistance to allow said portion tobe broken away from said skirt and thereby disengage said wall frominside said container neck.

3. An external and internal seal for containers such as bottles having aneck rim comprising:

an external cap including a skirt terminating in a lip,

said skirt flexed to firmly grip said rim with said lip frictionallyseated beneath said rim;

a Wall depending from said cap and protruding within said container insealing engagement with said neck;

a plurality of fins radially extending inwardly from said wall, each ofsaid fins radially terminating at separate locations within said wall toseat said wall against said container neck and to allow said wall to bereadily engaged and disengaged from said container neck; I

a tab projecting from said flared skirt; and

a thin wall section in said cap extending along a portion of said skirtto said tab and forming a path of least tearing resistance to allow saidportion to be broken away from said skirt and thereby disengage saidwall from inside said container neck.

4. An external and internal seal for containers such as bottles having aneck rim comprising:

an external cap including a skirt terminating in a lip, said skirtflexed to firmly grip said rim with said lip frictionally seated beneathsaid rim;

a wall depending from said cap and protruding within said container insealing engagement with said neck;

a plurality of fins radially extending inwardly from said wall, each ofsaid fins radially terminating at separate locations within said wall toseat said wall against said container neck and to allow said Wall to bereadily engaged and disengaged from said container neck; and

a thin wall section in said cap extending along a portion of said skirtand forming a path of least tearing resistance to allow said portion tobe broken away from said skirt and thereby disengage said wall frominside said container neck.

5. An external and internal seal for containers such as bottles having aneck rim comprising:

an external cap including a skirt terminating in a lip, said skirtflexed to firmly grip said rim with said lip frictionally seated beneathsaid rim;

a wall depending from said cap and protruding within said container insealing engagement with said neck;

a plurality of fins radially extending inwardly from said wall, each ofsaid fins radially terminating at separate locations within said wall toseat said wall against said container neck and to allow said wall to bereadily engaged and disengaged from said container neck; and

a thin wall section in said cap extending from above said neck rim andalong a portion of said skirt and forming a path of least tearingresistance to allow said Wall section to be broken away from said skirtand from above said neck rim to unseat said lip, the continued pullingof said wall section disengaging said wall from inside said containerneck.

6. An external and internal seal of resilient plastic material forcontainers such as bottles having a neck rim comprising:

a resilient external cap including a skirt terminating in a lip, saidskirt flexed to firmly grip said rim with said lip frictionally seatedbeneath said rim;

an integral tubular plug depending from said cap and having a wallprotruding within said container in sealing engagement with said neck;

a plurality of fins integral with said plug, each of said fins radiallyextending inwardly from said plug wall and terminating at separatelocations within said plug to seat said wall against said container neckand to allow said plug to be readily engaged and disengaged from saidcontainer neck;

an internal tab projecting from said skirt; and

a thin wall section in said cap extending from above said neck rim andalong a portion of said skirt to said tab and forming a path of leasttearing resistance to allow said wall section to be broken away fromsaid skirt and from above said neck rim to unseat said lip as said tabis pulled, the continued pulling of said tab thereby disengaging saidwall section from inside said container neck.

7. An external and internal seal of resilient plastic ma- 6 terial forcontainers such as bottles having a neck rim comprising:

a resilient external cap including a skirt gripping said rim;

5 a wall depending from said cap and protruding within said container insealing engagement with said neck;

a tab projecting from said skirt; and

a thin wall section in said cap having a thickness between 12% and 25%of the thickness ,of said skirt and of the adjacent portions of saidcap, said thin wall section extending along said skirt to said tab andthe junction of said thin wall portion alone being imperforate andforming tearing edges to allow the lifting of said tab to break awaysaid skirt and disengage said wall from inside said container neck.

8. An external and internal seal of resilient plastic material forcontainers such as bottles having a neck rim comprising:

an external cap formed of polypropylene including a skirt firmlygripping said rim;

an integral tubular plug depending from said cap and having a wallprotruding Within said container in sealing engagement with said neck;

an integral tab projecting from said skirt; and

a thin wall section in said cap having a thickness be tween 12% and 20%of the thickness of said skirt and of the adjacent portions of said cap,said thin wall section extending along a portion of said skirt and thejunction of said thin Wall portion alone being imperforate and formingtearing edges to allow said portion to be broken away from said skirtand thereby disengage said wall from inside said container neck.

9. An external cap seal formed of elastomeric material for containerssuch as bottles having a neck rim comprising:

an external cap forming a seal around said rim, said cap including thickand thin wall portions;

a gripping surface on one portion of said differential wall thickness toenable said portion to be torn away from the remaining portion of saidcap and thereby break said container seal, and the junction of said thinwall portion alone being imperforate and forming tearing edges to allowthe lifting of said gripping surface to disengage said thick and thinwall portions.

10. A cap seal formed of elastomeric material for containers such asbottles having a neck rim comprising:

an external cap forming a seal around said rim, said cap including adifferential wall thickness wherein a first portion of said wall isformed with a thickness between 12% and 25 of the remaining portion ofsaid wall,

said first wall portion having a gripping surface to enable said firstportion to be torn away from the remaining portion of said wall andthereby break said cap seal from said container and the junction betweenthe differential thickness wall portions alone being imperforate andforming tearing edges to allow the lifting of said gripping surface todisengage said differential wall portions from one another.

11. A cap seal formed of polypropylene for containers such as bottleshaving a neck rim comprising:

an external cap forming a seal around said rim, said 65 cap including adifferential wall thickness wherein a first portion of said wall has athickness between 12% and20% of the thickness of the remaining portionof said wall,

a gripping surface on said first wall portion to enable said firstportion to be torn away from the remaining portion of said wall andthereby break said cap seal from said container, and the junction ofsaid differential wall portions alone being imperforate and formingtearing edges to allow the lifting of said 7 8 gripping surface todisengage the differential wall 3,142,402 7/1964 Fox 215--46 XR portionsfrom one another. 3,186,736 6/1965 Sal-miner! 215-47 XR FOREIGN PATENTSReferences Cited 33 10/ 1958 F 69 9 rance 5 UNITED STATES PATENTS640,407 5/ 1962 Italy.

2,370,732. 3/1945 Johnson $215-40 3,032,226 5/1962 Terwilliger 215-46FRANKLIN T. GARRETT, Prin'zary Examiner.

1. AN EXTERNAL AND INTERNAL SEAL FOR CONTAINERS SUCH AS BOTTLES HAVING ANECK RIM COMPRISING: AN EXTERNAL CAP INCLUDING A SKIRT TERMINATING IN ALIP, SAID SKIRT FLEXED TO FIRMLY GRIP SAID RIM WITH SAID LIPFRICTIONALLY SEATED BENEATH SAID RIM; A WALL DEPENDING FROM SAID CAP ANDPROTRUDING WITHIN SAID CONTAINER IN SEALING ENGAGEMENT WITH SAID NECK; ATAB PROJECTING FROM SAID FLEXED SKIRT; AND A THIN WALL SECTION IN SAIDCAP EXTENDING ALONG SAID SKIRT TO SAID TAB FORMING A PATH OF LEASTTEARING RESISTANCE TO ALLOW THE LIFTING OF SAID TAB TO BREAK AWAY SAIDSKIRT AND DISENGAGE SAID WALL FROM INSIDE SAID CONTAINER NECK.